Dual Use Thermistor (bq24617 & bq27510)

TLHB

Other Parts Discussed in Thread: BQ27510, BQ24617, BQ24167

Could I use one thermistor for a system that uses the bq24617 charger and bq27510 gas gauge on the host side? The battery pack would have 3 leads coming out (P+, P-, TH) with one lead of the thermistor connected to P-. Would the thermistor being measured by two devices simultaneously have any negative affect on the readings?

over 14 years ago

0 Ming Yu over 14 years ago

TI__Expert 4050 points

TL, to Share the thermistor in the battery by charger and gauge are very tricky. Unless you can synch and isolate the measurement, two measurement at the same time will have problem with temp reading as the HW circuits are changed (the voltage divide ratio) which cause wrong temp reading,

Ming

0 TLHB over 14 years ago in reply to Ming Yu

Prodigy 105 points

Hi Ming,

If i use two thermistors, can they share the same return reference, i.e. P-? Or should they be isolated?

0 Ming Yu over 14 years ago in reply to TLHB

TI__Expert 4050 points

normally they should be isolated. If you have sch, we can review.

Ming

0 TLHB over 14 years ago in reply to Ming Yu

Prodigy 105 points

Hi Ming,

I am mistaken, the part number our customer is using is the BQ24167. Could you send a me a PM so i can go over the sch with you?

Thanks!

0 Jared Casey over 14 years ago in reply to TLHB

TI__Expert 4115 points

Hello TLHB,

I am helping out Ming with this issue. I have recently sent you a friend request so that we can correspond through PMs. If we can get your schematic we can review and go from there. Thank you.

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Dual Use Thermistor (bq24617 & bq27510)